Would watching a file for changes or redundantly querying that file be more efficient?

Question

I am wondering whether watching a file/directory for changes using the FileSystemWatcher class is extremely memory intensive. I am developing a desktop application in C# that will be running behind the scenes continuously on low-performance computers, and I need some way of checking to see if various files have changed. I can think of a few solutions:

1. Watch the directories using FileSystemWatcher.
2. Run a timed thread on an interval that goes through and manually checks this.
3. Check manually every time the actionhandler thread runs (the program will occasionally do something, on an action).

Any suggestions?

Thanks!

badPanda

Answer 1

Event-based are always more efficient than polling using the same or spawning a new thread, so it's the right idea to use FileSystemWatcher. The programming model, which uses delegates is also more elegant in my opinion.